<!DOCTYPE html>
<html>
  <head>
    <title>Private access</title>
  </head>
  <body onload='document.forms[0].elements[0].focus();' style='text-align: center; margin-top:100px'>
    <h1>Private access</h1>
    <form action="/" method="post">
      <p>
        <label for="private_code" style='display: none'>Secret code</label>
        <input type="password" name="private_code" placeholder="Secret code" />
        <input type="submit" />
      </p>
    </form>
  </body>
</html>